This invention relates generally to rockdrills. More particularly the invention relates to a filter for a rockdrill operable by a fluid under pressure for filtering the fluid to remove solid contaminants therefrom.
In deep mining operations such as in gold mines and platinum mines, a powering and cooling system is used which is referred to as hydropower. Hydropower serves the cooling and powering needs of deep underground mines by using open-loop circulation of chilled water. Water which accumulates in the sump of the mine is pumped to the surface, filtered, cooled and directed into a high-pressure vertical column which conducts the water underground. When tapped from the piping underground the high pressure water is used to cool, to generate electricity and to power various machines such as rockdrills. Because rockdrills typically have small operating clearances they are sensitive to contamination by dirty water from the hydropower system. Additionally, because the hydropower flow is on an open loop the water is filtered only on the surface before it enters the delivery and distribution piping. Various types of rockdrill inlet filters are known in hydropower systems, but due to size constraints, fluctuating levels of dirt, and resistance from operators to change filters, many of them have disadvantages. These known filters include the following:
i. Inexpensive disposable filters that are intended to be changed at the end of every drilling shift. These filters either clog too quickly, sometimes in the middle of a shift or the operators do not have the discipline to change them. Tampering of the dismantled filter is also difficult to prevent. PA0 ii. Steel edge wire filters that can be washed off are also known but they are not effective in removing embedded dirt. PA0 iii. Plate type in-line filters which can be dismantled and washed are also known. The additional weight of the in-line assembly is cumbersome and assembling and dismantling are difficult.
When a rockdrill filter clogs with dirt or malfunctions, performance is lost and typically the drill breaks down and causes an interruption in productivity.
The foregoing illustrates limitations known to exist in presently known water powered rockdrills. Thus, it is apparent that it would be advantageous to provide an alterative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.